The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

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-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

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Goodwill and Other Intangible Assets - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Finite-Lived Intangible Assets [Line Items]
Amortization expense related to the intangible assets	$ 82	$ 86	$ 86
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Expected amortization for the year 2013	80
Expected amortization for the year 2014	80
Expected amortization for the year 2015	80
Expected amortization for the year 2016	80
Expected amortization for the year 2017	80
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Expected amortization for the year 2013	90
Expected amortization for the year 2014	90
Expected amortization for the year 2015	90
Expected amortization for the year 2016	90
Expected amortization for the year 2017	$ 90